fix: add handlerProtocol key explicitly in handler metadata

Author: AllanZhengYP

packages/middleware-host-header/src/index.ts

@@ -32,10 +32,10 @@ export const hostHeaderMiddleware = <
 ): BuildMiddleware<Input, Output> => next => async args => {
   if (!HttpRequest.isInstance(args.request)) return next(args);
   const { request } = args;
-  const { metadata = [] } = options.requestHandler;
+  const { handlerProtocol = "" } = options.requestHandler.metadata || {};
   //For H2 request, remove 'host' header and use ':authority' header instead
   //reference: https://nodejs.org/dist/latest-v13.x/docs/api/errors.html#ERR_HTTP2_INVALID_CONNECTION_HEADERS
-  if (metadata.includes("h2") && !request.headers[":authority"]) {
+  if (handlerProtocol.indexOf("h2") >= 0 && !request.headers[":authority"]) {
     delete request.headers["host"];
     request.headers[":authority"] = "";
     //non-H2 request and 'host' header is not set, set the 'host' header to request's hostname.

packages/node-http-handler/src/node-http-handler.spec.ts

@@ -43,7 +43,7 @@ describe("NodeHttpHandler", () => {
     });
     it("has metadata", () => {
       const nodeHttpHandler = new NodeHttpHandler();
-      expect(nodeHttpHandler.metadata).toContain("h1");
+      expect(nodeHttpHandler.metadata.handlerProtocol).toContain("http/1.1");
     });
     it("can send http requests", async () => {
       const mockResponse = {

packages/node-http-handler/src/node-http-handler.ts

@@ -33,7 +33,8 @@ export class NodeHttpHandler implements HttpHandler {
   private readonly httpsAgent: https.Agent;
   private readonly connectionTimeout?: number;
   private readonly socketTimeout?: number;
-  public readonly metadata = ["h1"];
+  // Node http handler is hard-coded to http/1.1: https://github.com/nodejs/node/blob/ff5664b83b89c55e4ab5d5f60068fb457f1f5872/lib/_http_server.js#L286
+  public readonly metadata = { handlerProtocol: "http/1.1" };
 
   constructor({
     connectionTimeout,

packages/node-http-handler/src/node-http2-handler.spec.ts

@@ -45,7 +45,7 @@ describe("NodeHttp2Handler", () => {
   });
 
   it("has metadata", () => {
-    expect(nodeH2Handler.metadata).toContain("h2");
+    expect(nodeH2Handler.metadata.handlerProtocol).toContain("h2");
   });
 
   describe("connectionPool", () => {

packages/node-http-handler/src/node-http2-handler.ts

@@ -27,7 +27,7 @@ export interface NodeHttp2Options {
 
 export class NodeHttp2Handler implements HttpHandler {
   private readonly connectionPool: Map<string, ClientHttp2Session>;
-  public readonly metadata = ["h2"];
+  public readonly metadata = { handlerProtocol: "h2" };
 
   constructor(private readonly http2Options: NodeHttp2Options = {}) {
     this.connectionPool = new Map<string, ClientHttp2Session>();

packages/types/src/transfer.ts

@@ -10,10 +10,16 @@ export interface RequestHandler<
    * 'h2' refers this handler is for handling HTTP/2 requests,
    * whereas 'h1' refers handling HTTP1 requests
    */
-  metadata?: Array<string>;
+  metadata?: RequestHandlerMetadata;
   destroy?: () => void;
   handle: (
     request: RequestType,
     handlerOptions: HandlerOptions
   ) => Promise<RequestHandlerOutput<ResponseType>>;
 }
+
+export interface RequestHandlerMetadata {
+  // This infers request handler's protocol
+  // valid values are stated: https://www.iana.org/assignments/tls-extensiontype-values/tls-extensiontype-values.xhtml#alpn-protocol-ids
+  handlerProtocol: string;
+}